NAVFAC P-433 Welding Materials Handbook_5 pdf

TRACTOR PARTS AND ACCESSORIESContinued Drive Sprockets Carbon Steel Primary Electrode: Page 1-24 Alternate Electrodes: Pages 1-5, 1-3 Welding Procedures: Position sprocket for downhand w

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TRACTOR PARTS AND ACCESSORIES

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Drive Sprockets

Carbon Steel

Primary Electrode: Page 1-24

Alternate Electrodes: Pages 1-5, 1-3

Welding Procedures: Position sprocket for downhand

welding Use buildup material on badly worn areas

(Figure 2-9) Use template to obtain proper shape

Grind high spots

FIGURE 2-9 Hard-Facing Drive Sprockets

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Tractor Grousers

Carbon Steel

Primary Electrode: Page l-25

Alternate Electrodes: Pages l-22,1-20

Welding Procedures: Anneal induction-hardened

grousers before welding bar stock on grousers (Do not

hardface new grousers) Rebuild cleat to original

height by welding steel reinforcing bar stock to pad

with appropriate electrode on page 1-3 Mark grouser

lengths for three equal parts (Figure 2-10) Face outer

thirds by beginning passes from center and working

out Entire length of grouser can be faced if desired,

but method shown avoids stress buildup

FIGURE 2-10 Hard-Facing Tractor Grousers

Ripper Teeth Carbon Steel Primary Electrode: Page 1-26 Alternate Electrodes: Pages 1-25, 1-22 Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com

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Ripper Teeth (Continued)

Welding Procedures: Apply to top and sides of tooth

covering area about 2 in back from point Hard-face

remainder of tooth as shown in Figure 2-11

FIGURE 2-11 Hard-Facing Ripper Teeth

Bulldozer End Bits Carbon Steel Primary Electrode: Page 1-25 Alternate Electrodes: Pages 1-22, 1-20 Welding Procedures: Place end bit in flat position and apply beads across outer comer and along edges On worn end bits, weld new corner and hard-face (Figure 2-12) If work involves impact, use above mentioned electrodes; in case of severe abrasion and moderate impact, use electrode on page 1-26

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Bulldozer Blades Carbon Steel Primary Electrode: Page 1-25 Alternate Electrodes: Pages 1-22, 1-20 Welding Procedures: Position blade in suitable prehending jig or where necessary, bolt blade to moldboard Use skip weld technique Apply stringer beads to make deposit 1-1/2 in wide (Figure 2-13) If work involves impact, use electrode on page 1-25; in case of severe abrasion and moderate impact, use electrode on page 1-26 which provides maximum service life NOTE: HIGH CARBON BLADES MUST BE PREHEATED BEFORE HARD FACING

FIGURE 2-12 Hard-Facing Bulldozer End Bits

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FIGURE 2-13 Hard-Facing Bulldozer Blades

Riper Shanks

Carbon Steel

Primary Electrode: Page 1-26

Alternate Electrodes: Pages 1-25, 1-22

Welding Procedures: Some ripper shanks are made of difficult-to-weld steels but can be protected without ever striking an arc on the base metal by fabricating a sleeve that fits tightly around the shank Cut side and back panels from 1/2 in mild steel plate; use 1 in plow steel for front panel Join front and side panels with mild steel electrodes and slip unit around shank (Figure 2-14) Weld back panel in place For manual welding, apply above-mentioned electrodes in waffle pattern on front panel and on side panels Shanks made of weldable steels can be protected by applying same patterns directly on base metal

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Rock Rake Carbon Steel Primary Electrode: Page 1-26 Alternate Electrodes: Pages 1-22, 1-20 Welding Procedures: Hard-face rock rake teeth when new for best service life Deposit electrode in slight weave beads running parallel to flow of rock; overlay top and sides of each tooth with heavy wash pass about

2 in from tip Do not allow teeth to wear more than 1/4 in before rehard-facing (Figure 2-15)

FIGURE 2-14 Hard-Facing Ripper Shanks

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FIGURE 2-15 Hard-Facing Rock Rake Teeth

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FIGURE 2-16 Shovel Parts and Accessories

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SHOVEL PARTS AND ACCESSORIES

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Shovel Rollers

Carbon Steel

Primary Electrode: Page l-24

Alternate Electrodes: Pages l-5,1-3

Welding Procedures: Construct jig so roller can be

turned for downhand welding Rebuild with buildup

material to original size (Figure 2-17).

FIGURE 2-17 Hard-Facing Shovel Rollers

Shovel Track Pads Carbon Steel Primary Electrode: Page 1-24 Alternate Electrodes: Pages 1-5, 1-3 Manganese Steel

Primary Electrode: Page 1-22 Alternate Electrodes: Page 1-25 Welding Procedures: Start application on lugs With manual process, rebuild worn areas to original size with recommended buildup material (Figure 2-18) Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com

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FIGURE 2-18 Hard-Facing Shovel Track Pads

Shovel Idlers

Carbon Steel

Welding Procedures: Construct jig so idler can be turned for downhand welding

Rebuild with buildup material to original size (Figure 2-19)

FIGURE 2-19 Hard-Facing Shovel Idlers

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Shovel Drive Tumblers

Carbon Steel

Manganese Steel

Alternate Electrodes: Page l-20

Welding Procedures: Construct jig so tumbler can be

turned for downhand welding Rebuild with buildup

material to original size Use template to obtain proper

size (Figure 2-20)

FIGURE 2-20 Hard-Facing Shovel Drive Tumblers

Shovel House Rolls Carbon Steel Primary Electrode: Page 1-24 Alternate Electrodes: Pages 1-5, 1-3 Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com

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SHOVEL PARTS AND ACCESSORIES Shovel and Dragline Buckets

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Selection of one weld pattern over another when Welding Procedures: House rolls are generally made hard-facing shovel and dragline buckets is important

of high carbon steel and should be preheated to at least One hard-facing alloy will not work satisfactorily 500°F Mount roll on jig for downhand welding under all wear conditions Likewise, one hard-facing Rebuild worn rolls with recommended buildup

material in transverse beads across face Machine or

grind to proper size (Figure 2-21)

FIGURE 2-21 Hard-Facing Shovel House Rolls

pattern will not perform the same under all wear

-conditions

A bucket working in sand with hard-facing beads applied at right angles to the flow of material will have

a longer service life than one with beads applied parallel to the flow

A waffle pattern of beads gives even better protection

to a bucket because the pattern forms small pockets where damp dirt becomes packed This results in abrasive soil working against more soil Both the hard-facing and the base metal are thus protected

A bucket working in dry, large-sized slag with hard-facing beads applied at right angles to the flow of material will be subjected to high abrasive wear Beads applied in the same direction of flow will, in this case, allow slag to ride on top of the hard metal beads Simpo PDF Merge and Split Unregistered Version - http://www.simpopdf.com

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without imposing wear on the base metal between the

beads

Another effective hard-facing pattern is the use of

small dots of hard metal alloy spaced close together

This method produces an effective hard-facing pattern,

while reducing the heat input from the welding

operation Chance of overheating high grade steel

used in some buckets is practically eliminated

The dots arc first applied on wide centers, the welder

gradually fills in the spaces until the area to be

hard-faced is covered with closely spaced dots of hard

metal (Figure 2-22)

Successful hard-facing patterns are found by trial and

error What works in one instance may not in another

Knowing the type of wear encountered, how it is

imposed, and the proper alloy to use, will help to apply

the most effective bead pattern Check the service life

received and the wear pattern developed Next time

hard-facing is applied, alter the pattern as required and check results against previous application

Recommended Alloys:

For relatively moderate wear, use electrodes on page 1-25 as a primary choice, and electrodes on page 1-22,

or 1-27 as alternate choices For extreme abrasion, use electrodes on page 1-26 as a primary choice and electrodes on pages 1-27 or 1-22 as alternate choices Skip weld on manganese buckets to avoid

overheating Where possible, position for downhand welding

Wear Plates:

Use stainless steel electrodes on page 1-20 to weld wear plates to worn buckets For best service life, hard-face wear plates as described above

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SHOVEL PARTS AND ACCESSORIES (Continued)

FIGURE 2-22 Hard-Facing Shovel and Dragline Buckets

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Shovel Teeth

Hard-face shovel teeth when they are new, before

putting them in service The weld bead pattern used on

shovel teeth can have a marked effect on service life

Teeth working primarily in rock should be hard-faced

with beads running the length of the tooth to allow the

rock to ride on the hard metal beads When working in

dirt, clay or sand, run the beads across the flow of

material (Figure 2-23) so it will fill cavities between

the weld beads and give the base metal added

protection Another effective pattern is the waffle or

cross hatch (Figure 2-24) Apply hard-facing to the

top and sides of the tooth 2 in up from point Stringer

beads behind a solid deposit reduces wash (Figure

2-25) Where abrasion and impact are extreme, use

electrodes on pages 1-25, 1-22, or 1-20 In cases

where impact is moderate and abrasion severe, use

electrodes on pages 1-26, 1-25, or 1-22

FIGURE 2-23 Hard-Facing Shovel Teeth

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Repainting Shovel Teeth:

Weld manganese repointer bars to manganese teeth with electrodes on page 1-22 or page 1-20 Weld carbon steel bars to carbon steel teeth using electrodes

on page 1-3, 1-1, or 1-2 Weld dissimilar metals (for example, manganese bars to carbon steel teeth) with stainless electrodes on page 1-20 Hard-face repointed teeth

Shovel Bucket Tooth Adapters Carbon Steel

Primary Buildup Electrode: Page 1-24 Primary Hard-Face Electrode: Page 1-25 Alternate Buildup Electrodes: Page 1-5, 1-3, 1-22, or 1-20

FIGURE 2-24 Repainting Shovel Teeth

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FIGURE 2-25 Comparison of Hard-Facing Patterns for Shovel Teeth

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